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For years, I've accepted Tom Van Flandern's proof, and others like it, that gravity is billions of times faster than light. That proof is based on the claim that we see the sun where it was, not where it is. I am now having second thoughts. Of course the Sun is where it was 8 minutes ago, in Solar coordinates. I'm referring to the direction relative to the stars, which goes thru 360° degrees in a year. In 8.3 minutes, the direction of the Sun from Earth changes by .0057°. So do we see the light coming from .0057° east of its current location? If we were moving in a straight line past the Sun, I believe that would be the case. I have read that a term in general relativity almost exactly cancels the direction change of the light, as if the centers of successive light pulses follow the source. The direction where we see an expanding spherical shell of light is perpendicular to the surface of the shell as it passes us. If we were in a circular orbit, I think the change in our direction, relative to the stars, would put the Sun's image back where the Sun is. I wonder if this analogy corresponds to the mysterious term in GR. Our orbit is elliptical, and if I'm right, the angle between where we see the Sun and where it is ought to go thru an annual cycle. Concentric light spheres spreading from the Sun are always tangent to a circular orbit, but only tangent to an elliptical orbit at aphelion and perihelion. If I now discard the idea that gravity is billions of times faster than light, there will need to be some changes in my model. I still think gravity is faster than light, but I'll have to look for a different proof and a different estimate of cg/cl.
Demonstrable we observe the Sun in the present in its present relative position to the observer.
Not possible. What you see is light that emanated from the sun about 8 minutes ago, so by the time you see it, the earth will have revolved about 2 degrees from where it was when the light left the sun. So when the sun appears to be overhead London, it is actually overhead Gloucester.
They usually do, until they learn to lead on a moving target. Ask any game or clay pigeon shooter! It's a particularly difficult skill for air gunners: if your bullets are travelling at 1000 mph and your target is crossing at 600 mph, you need to be very good at mental arithmetic, which is why antiaircraft shells and guided missiles use proximity fuses, and successful ship-to-air gunnery often consists of just letting everything rip at once.
The Box alancalverd is correct. You do not understand simultaneity of relativity.
Relative time is the same. You view revolutions in relative time of course but the image takes light years to get here. A recording through time.
Consider the light from an object takes the same time to reach an observer as the observers light to reach the object being observed, there is no time discrepancy. The position is fixed to each other .
Quote from: GoC on 24/12/2015 21:49:51Relative time is the same. You view revolutions in relative time of course but the image takes light years to get here. A recording through time.I don't agree . The physics would be all wrong when considering trajectories etc. Consider the light from an object takes the same time to reach an observer as the observers light to reach the object being observed, there is no time discrepancy. The position is fixed to each other .
The very fact that light takes time to travel means we don't see objects in their local time. In the other direction they don't see us in our local time either. This is just the same as the time taken for sound to travel, we don't hear in local time either.What you are forgetting for air rifles is that the speed of light is so fast and the distance so short that we can ignore the delay. Over space distances we can't.